DURHAM, N.C. — Durham police returned to Mike Peterson's home on Thursday.

Detectives were at Peterson's home throughout Thursday, taking additional measurements of the staircase, where Peterson's wife, Kathleen, was found dead in December 2001. Those measurements will be used to help wrap up reports for their investigation.

Peterson has been charged with his wife's murder. He has maintained that Kathleen accidentally fell down the staircase and that he is innocent of any wrongdoing.

Months ago, forensic specialist Dr. Henry Lee, who gained notoriety for his work in the O.J. Simpson case, was at Peterson's house, taking measurements for the defense team. That stairwell has been boarded up and sealed as evidence since Kathleen's death.

During a court hearing last month, the district attorney asked the judge if his team could take additional measurements of the crime scene. The judge granted that request. David Rudolf, Mike Peterson's attorney, did not oppose the request.

The case is scheduled to go to trial in May.